Recent conveying devices have a large number of conveying passages for conveying an article in various directions. On the other hand, an area where the conveying device is installed, such as in a factory, is limited, and a large number of the conveying passages are disposed in this limited area. Therefore, it is not easy for a worker, a carrier, or a work vehicle such as a forklift to move inside the conveying device.
Conventionally, a connecting stair or a flip-up conveyor device has been installed in order to enable a worker or a work vehicle to move inside the conveying device.
Although the worker can pass through the connecting stair, the work vehicle cannot pass through the connecting stair. Additionally, the flip-up conveyor device is installed adjacent to a fixed conveyor device, and a flip-up movable section in the flip-up conveyor device moves above the fixed conveyor device. Therefore, a space for enabling the flip-up movable section to move has to be provided above the fixed conveyor device. Additionally, large power for operating the flip-up movable section is required.
In order to solve these problems, it is considered that a first conveying passage and a second conveying passage are connected by an extendable conveyor device.
That is, when the whole length of the conveyor device is extended, the first conveying passage and the second conveying passage are connected, and an article can be conveyed. When the whole length of the conveyor device is contracted to be shortened, the first conveying passage and the second conveying passage are cut, and it is possible to form a space through which a worker or a work vehicle can pass. Additionally, the extendable conveyor device does not need to provide a space above the fixed conveyor device
However, according to examination conducted by the present inventors, such a conventional technology cannot be found, and Patent Document 1 similar to the conventional technology has been found.